High intensity lighting means



Aug. 6, 1940. w. c. 'H EB 2.210.537

men INTENSITY LIGHTING MEANS Filed Nov. 26, 1938 2 Sheets-Sheet 1 27 INVENT'UR WIN/0m G/eimzr ATTORNEY Aug. 6, 1940. w. c. HUEBNER HIGH INTENSITY LIGHTING BANS Filed Nov. 26. 1938 2 Sheets-Sheet 2 FIELE- INVENTEIR W ///"am Hue &/1V E1 AT TDRNEY Patented Aug. 6, 1940 UNITED STATES PATENT OFFICE 4 Claims.

This invention relates to improvements in high intensity lighting means and more especially, but not exclusively, such lighting means for use in'the graphic arts for making direct expoa sures to metal plates in direct projection work, for photomechanical plate making, for printing cylinders, for illuminating copy in process cameras, and for use with printing frames.

Heretofore, in direct projection to metal press plates, it has been almost the universal practice to employ arc lights in conjunction with condensing lenses. In such practice, the images projected or enlarged to the surface of the metal press plate tend to fade away and lose sharpness at the four corners of the enlargements. In those cases where half tone dots are projected, the dots carry a color fringe caused by the optical system, which fringe is increased by the flickering of the arc flame due to the air ourrents set up and breakage of the carbons. Such flickering movements of the flame are naturally accentuated by the projection lens, with corresponding effect on the edges of the projected dot images.

One object of this invention, therefore, is to provide a lighting means or an arrangement that will provide a more concentrated and intense light than any heretofore used for obtaining actinic action on sensitized elements in the graphic arts and wherein the light source proper is steady, free from vibration, fluctuation and flickering, all to the end that sharper images and better results are obtained than heretofore.

Another disadvantage inherent in the arc light arrangements heretofore used in direct projection work, photo composing and the like in the graphic arts where intense lighting has been necessary, results from the intense heat generated by the arc lights, which is'frequently so great as to soften the gelatin on dry plates and cause breakage of glass plates. Also, as well known, the lenses used for projection in the class of work referred to, have their component parts cemented together, and it has been found that the heat generated by the arc lights tends to gradually melt Y the cement with consequent breakdown of the focusing efficiency of the lenses. While it has been customary to try and dissipate such heat from the arc lights by the use of fans, experience has shown that the injurious effects from heat, .as above mentioned, cannot be successfully overcome.

Another object of the invention is to provide lighting means of the type indicated in the pre- 25 ceding object of invention characterized by the fact that all deleterious efiects of heat from the lighting source proper on lenses, plates and sensitive coatings are eliminated.

A still further object of the invention is to provide a lighting means of the character indicated in the foregoing objects of invention such that a plurality of lighting units may be employed and so arranged and adjusted as to give any desired degree of concentration or diffusion of the light.

Other objects of the invention will more clearly appear from the description and claims hereinafter following.

In the drawings forming a part of this specification, Figure 1 is a front elevational view of a lighting apparatus showing one embodiment of the invention, the lighting units proper in this arrangement being shown closely. spaced for a high degree of concentration of the light beam to be emitted. Figure 2 is a vertical sectional view, corresponding substantially to the line 2-2 of Figure 1. Figure 3 is a view similar to Figure l but showing a relatively widely spaced relation of the three lighting units and with the reflector omitted to obtain an intense but more diffused lighting effect. Figure 4 is a vertical sectional view, corresponding substantially to the line |4 of Figure 3. Figure 5 is a view similar to Figure 2, but illustrating a modified form of the invention employing a greater number of lighting units for an intense and highly concentrated light effect. And Figure 6 is a diagrammatic view illustrating one mode of utilizing the invention in connection with direct projection work.

Referring first to the construction illustrated in Figures 1 to 4, A designates a supporting frame which may be of any suitable construction. As shown, the same is of rectangular outline from the corners of which extend rearwardly four posts I 0-40, the latter having secured thereto, at their rear ends, a spider H with a central circular opening l2. Detachably secured to the spider II, is an annular shell l3, as by the thumb screws I4-l4. The shell l3 in turn has secured thereto a reflector 15 which, as shown, comprises a portion of a spherical surface.

Carried by the frame A is a plurality of water cooled mercury vapor lamp units indicated at l5, l1 and I8, three in number as in the form illustrated in Figures 1 to 4. Each of said units comprises, broadly, an inner cylindrical vapor tube IS, an outer cylindrical and concentric water tube 20 and suitable end fittings 2l-2| through which are entered the electric conductors and the water for cooling. Each said unit is mounted on a pair of rods 22-22, one at each end thereof and secured to the end fittings 2I.

' The upper unit I 6 has its supporting rods 22 vertically, slidably, adjustably mounted in the top cross arm of the frame A, the unit being secured in any desired adjusted position, as by the pair of thumb screws 2323. The lower unit I1 is similarly mountedin the bottom cross arm of the frame A, as clearly shown in the drawings. With this construction it will be seen that the two units I6 and I! are relatively adjustable toward and from each other in a vertical plane, which plane is perpendicular to the lines of emitted light rays from the reflector I5, or what may be termed the focal axis of the reflector, which, as shown in Figures 1 and 2, extends horizontally. The necessary electric current for the units is supplied through suitable conductors properly insulated in the rods 22, the latter being provided with suitable terminals 24-24 for attaching the wires from an outside source of current.

The third unit I8 is similarly mounted on a pair of supporting rods 25-25 attached to a shaft 26, rotatably adjustably mounted in a slide block 21, the shaft being adapted to be clamped in any angularly adjusted position by means of a split collar 28 and thumb screw 29. The slide block 21 is horizontally slidably adjustable on the bottom cross arm of the frame A, as shown. As will also be understood, the supporting rods i5 for the unit I8 are endwise adjustable rela tive to the shaft 26, thus providing for adjustment of the unit I8 both up and down in directions parallel to the'plane of the two units I6 and I1 and angularly toward and from said plane, as indicated by the dash line are a: in Fignresland 4. As'willbe apparent from an inspection of the drawings, the length vof all of the vapor tubes I9 and water tubes 20 is relatively short and less than the maximum distance across the reflector I5 and, further, the axes of all of the vapor lamp units are arranged and at all times maintained parallel.

Water for cooling the mercury tubes is supplied through a flexible hose or pipe 30, the water entering the lower unit I? through the right hand end fitting 2I thereof and emerging from the left hand end where the water is passed through a flexible tube or pipe 3| and conductedinto the left hand end of the middle unit I8. From the latter, the water is conducted through another flexible tube or pipe 32 to the right hand end of the unit I 6 and thence from the latter out through the tube or pipe 33 to a suitable drain. With this hookup of water cooling system, it is evident that the necessary adjustments of the lamp units may be made without disconnecting any of the water line.

With the construction so far described, it is apparent that the plurality of units may be adjusted with their axes very closely together, as

- shown in Figures 1 and 2, wherein all three lamp units are well within the area, considered horizontally projected, of the reflector I5 and the rays of light given out on the right hand side of the units, as viewed in Figure 2, will be picked up and reflected in a concentrated beam by the reflector I5 toward the left, thus giving an extremely high intensity of light and highly concentrated. With the construction and arrangement disclosed, the efi'ect' produced is that of a substantially single light point which is particularly adapted for use in a condenser projection system to provide a field of uniform light on a fiat plane and thereby insure sharp detail over the area occupied by the projected image. Furthermore, by utilizing water cooled mercury vapor lamps of the character indicated, very little heat is given off to the atmosphere, thus eliminating danger of melting the sensitive coatings or injuring lenses or cracking any glass plates that may be employed in the projection or composing process. Figures 3 and 4 illustrate the positions of the units when it is desired to obtain a more diffused lighting effect. And it is obvious that various other settings of the lamp units may be employed within the range of adjustments of the units. Further, on account of the type of lamp units employed, there is no flickering or vibration of the light beam emitted, but, on the contrary, a constant and steady uniform light, which, in actual practice, has given far better results with sharper images than'heretofore possible with any other known type of lighting system employed in the graphic arts.

Referring to the construction in Figure 5, five water cooled mercury vapor lamp units are employed, designated H6, H1, H8 and 4040.

Those referenced H6 and II! are mounted similar to those referenced I6 and I! of the first described form. The unit I I8 is adjustably mounted to provide for the two adjustments up and down and angularly toward and from the reflector II5 with the difference that the shaft I26 thereof is carried by a slide block 4| inwardly and outwardly adjustable on an arm 42 of the supporting frame. The other two units 40-40 are relatively vertically adjustable in a plane inwardly of the vertical plane defined by the units I I6, I I1. Said units 40 are supported from slide blocks 43-43 mounted on an upper bracket 44 carried by the upper cross arm of the frame A and the lower slide block 43 is adjustably mounted horizontally on the lower arm 42 carried by the frame. Said units 4040 are also preferably angularly adjustable as by means of the shafts 45 mounted in the split clamps of the respective slide blocks 4343. A similar arrangement is employed for supplying the cooling water, the

inlet pipe being indicated by dotted lines at I30 and the outlet pipe at I33 with suitable flexible connectors I3I between each adjacent pair of units, thus providing for the necessary flexibility of adjustment. With the arrangement shown in Figure 5, an exceedingly high concentration of light of intense power may obviously be obtained, and even though the units are brought relatively close to each other, the heat is amply dissipated by the water cooling system, as will be apparent. In this arrangement, the reflector H5 is preferably made vertically adjustable on a standard 46, which in turn is horizontally adjustable on the arm 42.

As will be apparent to those skilled in the art, various changes in details of construction may obviously be made without departing from the spirit of the invention. I

In the diagrammatic view of Figure 6, the reflector is indicated conventionally at 2I5 and the series of five units at 2I6 with the light adapted to be projected along the axis y initially through the condensing lenses 5Il50, then through the image plate 5I, next through the projector lens 52 and finally the image impressed upon the sensitized plate 53 greatly enlarged as. in direct projection work.- As will be apparent to those skilled in the art, the improved lighting arrange.-

ment may be employed in photo composing machines for preparing both flat plates and cylindrical surfaces; for illuminating copy in process cameras, in printing frames and for similar uses in the graphic arts.

What is claimed is:

1. In a high intensity lighting device adapted for use in a condenser projection system for photomechanical work, the combination with a frame; of a plurality of water cooled mercury vapor lamp units, each unit comprising a tubular structure; supporting devices, individual to each of said units and on which the respective units are mounted, all of said devices being so arranged that the axes of all the tubular structures are disposed parallel to each other; means adjustably attaching said supporting devices for two of said lamp units to the frame, said means being adjustable to move the lamp units toward and from each other in a plane defined by the parallel axes of said two lamp units; and additional means adjustably attaching the supporting device of a third lamp unit to the frame, said last named means being adjustable to move its lamp unit both in a plane parallel to the first named plane and also toward and from said first named plane, whereby all three lamp units may be brought into close proximity with their axes parallel to thereby produce a concentrated substantially single light source or separated to provide a diffused source of light.

2. In a high intensity lighting device adapted for use in a condenser projection system for photomechanical work, the combination with a frame; of a plurality of water cooled mercury vapor lamp units, each unit comprising a tubular structure; flexible conduits connecting the respective lamp units whereby the cooling water is circulated through the lamp units in series; supporting devices, individual to each of said units and on which the respective units are mounted, all of said devices being so arranged that the axes of all the tubular structures are disposed parallel to each other; means adjustably attaching said supporting devices for two of sid lamp units to the frame, said means being adjustable to move the lamp units toward and from each other in a plane defined by the parallel axes of said two lamp units; and additional means adjustably attaching the supporting device of a third lamp unit to the frame, said last named means being adjustable to move its lamp unit both in a plane parallel to the first named plane and also toward and from said first named plane, whereby all three lamp units may be brought into close proximity with their axes parallel to thereby produce a concentrated substantially single light source or separated to provide a diffused source of light.

3. In a high intensity lighting device adapted for use in a condenser projection system for photomechanical work, the combination with a frame; of of reflector mounted on said frame; a plurality of water cooled mercury vapor lamp units, each unit comprising a tubular structure the length of which is less than the maximum, distance across the reflector; supporting devices, individual to each of said units and on which the respective units are mounted; all of said devices being so arranged that the axes of all the tubular structures are parallel; means adjustably attachin said supporting devices for two of said lamp units to the frame, said means being adjustable to move the lamp units toward and from each other in a plane defined by the parallel axes of the two lamp units; and additional means adjustably attaching the supporting device of a third lamp unit to the frame, said last named means being adjustable to move its lamp unit in directions both parallel to said plane and also toward and from said plane whereby all three lamp units may be brought into close proximity with their axes parallel and disposed within the area, considered projected toward the lamp units, of the reflector, to thereby produce a concentrated single light source in effect or separated to provide a diifused source or light.

.4. In a high intensity lighting device adapted for use in a condenser projection system for photomechanical work, the combination with a frame; of a reflector supported on said frame; a pair of water cooled mercury vapor lamp units disposed in front of the reflector, each unit comprising a tubular structure with their axes arranged parallel in a plane perpendicular to the focal line of projection of the reflector; means adjustably connecting said lamp units to the frame to move the lamp units toward and from each other in said plane; a second pair of similar water cooled mercury vapor lamp units disposed with their axes parallel and in a plane parallel to the first named plane; means adjustably attaching said last named pair of lamp units to the frame to permit adjustment of the lamp units toward and from each other in their corresponding plane; a fifth similar water cooled mercury vapor lamp unit having its axis disposed parallel to the axes of the other lamp units; and means adjustably connecting said fifth lamp unit to the frame to move angularly toward and from the planes defined by the first named pairs of units.

WILLIAM C. HUEBNER. 

